1. Field
The present invention relates to compression and/or decompression of a data set using significance mapping.
2. Background Information
As is well-known, compression and decompression of data signals is employed in a variety of circumstances. Vector quantization is a well-known technique to achieve high performance signal compression. For example, although the invention is not limited in scope in this respect, it may be desirable to compress video signals, such as an image, a sequence of images, audio signals, or any combination thereof. Compression may typically be employed for purposes of storage or in order to transmit signals over a limited bandwidth communication link, although the invention is not limited in scope in this respect.
Many forms of compression suffers from several disadvantages. For example, compression is typically computationally complex. Therefore, compression techniques that are less computationally complex are sometimes desirable. Likewise, compression is not typically adaptable to achieve a particular bit rate, as may be desirable in some circumstances, such as where transmission is taking place over a limited bandwidth communications link, for example. Therefore, a need exists for compression techniques that address these shortcomings.
Briefly, in accordance with one embodiment on the invention, a method of compressing a data set includes the following. In multiple passes, each data signal in the data set is categorized into a category of a predetermined set, and, for selected categories of the predetermined set, the data signals for that category are coded using a codebook for that category.
Briefly, in accordance with another embodiment of the invention, a method of decompressing a compressed data set includes the following. For compressed data signals in the data set in one category of a predetermined set of categories, a signal associated with the particular category is employed for the compressed data signal, and, for selected categories of the predetermined set, the compressed data signals for that category are decoded using a codebook for that category.